A water use and wastewater reuse program has been developed for the Ecovillage that will incorporate best practices in sustainable infrastructure and water management. We have committed that the new Ecovillage development will not use more groundwater than has historically been extracted by the Pacific Union College system, even at build-out of the Ecovillage.
Our comprehensive program introduces the use of recycled wastewater, springwater and rainwater to meet the irrigation demands, and implements a host of water use reduction measures for the new development and for existing PUC facilities. The wastewater treatment and water use program for the Ecovillage represents a commitment to a sustainable water supply in the Angwin watershed.
On the following pages, we will detail the measures included in our plan that incorporate water efficient principles and wastewater reuse for the Ecovillage and the existing PUC service area.
Sustainable Water Use Strategies
Reduction in the indoor use of potable water for the Ecovillage and PUC’s existing buildings will be achieved through the installation of water efficient fixtures and fittings (faucets, toilets, urinals, showers) and high efficiency appliances (dishwashers and washing machines). The Ecovillage’s Office of Sustainability will provide literature and consultation to encourage and support a lifestyle of water conservation for Ecovillage residents and the PUC community.
Wastewater Treatment and Wastewater Reuse
The greatest reduction in potable water demand will be realized by providing an alternative water source for landscaping and agricultural irrigation systems. This will be achieved through treating wastewater to such a cleansing level that it can be used for these purposes. The existing wastewater treatment facility will be upgraded to provide water treated to a disinfected tertiary treatment standard, the highest level covered by California Standards. Currently, the wastewater treatment facility treats wastewater to a secondary standard and stores it within a reservoir east of the airport, for use only on animal feed crops. The Ecovillage upgrade will continue to store recycled water in the existing reservoir, however the upgrade in treatment will allow the water to be used for irrigation of PUC landscaping, Ecovillage agricultural areas, Ecovillage landscaping and recreational areas in accordance with Title 22 Regulations.
There are several wastewater treatment/wastewater reuse programs in operation throughout the state of California, and approximately half of the water reclaimed by these programs is used for agricultural irrigation, with 20% used for landscape irrigation. These projects are helping preserve the state’s drinking water supply while providing agricultural and irrigation users with a drought-resilient water supply. The latest available figures from 2002, indicate that over 176 billion gallons of recycled water, roughly five times the annual use of the city of San Francisco, was used throughout the state, and that quantity continues to increase.
The Napa Sanitation District (NSD) is dedicated to the use of recycled wastewater and has documented using 700 million gallons supplying 1,575 acres of land in 2004, as stated in the Strategic Plan for Recycled Water Use in the Year 2020 published by the NSD. The Soscol Water Recycling Facility, which is the main facility within Napa County, has been using recycled water to irrigate golf courses since 2003. Currently, NSD is investigating plans to upgrade the wastewater facilities throughout Napa County with the ultimate goal of being able to service the irrigation needs of 10,000 acres of land by 2020 through disinfected tertiary recycled water.
Springwater and Rainwater Harvesting
Springwater capture and rainwater harvesting are other alternative sources that can be used to supplement the recycled wastewater to service irrigation needs.
The Ecovillage will continue PUC’s current practice of harvesting springwater from water courses that feed into Conn Creek during the spring and summer for irrigation purposes.
The natural watershed of the storm drainage system is extensive, and offers the opportunity to capture large amounts of rainwater for storage and future irrigation use. The rainwater will be stored in the reservoir and used as an irrigation source during the summer to offset the use of groundwater for irrigation purposes. Rainwater harvesting is especially common in the northwest in cities like Seattle and Portland where there is a need to preserve natural water bodies, and to meet irrigation demands within the summer months.
Landscape Irrigation Water Use
PUC’s irrigation network is extensive and constitutes over 50% of current water use. In the past year the network has been upgraded to be more water efficient with the implementation of a centralized computerized control system to manage irrigation throughout the campus. This system offers several advantages when compared to the previous system including computerized controls, and automatic shutoff switches during rain storms, leading to significant water savings. Other irrigation reduction technologies such as moisture sensors and drip irrigation will be implemented where feasible and will further improve the efficiency of the irrigation systems.
Stormwater Management
The Ecovillage will embrace best practice measures for stormwater management to encourage the infiltration and recharge of the groundwater system. Naturalized systems such as street-side swales, raingardens, permeable pavement and other stormwater management devices can be used to naturally retain, treat and filter stormwater before entering the groundwater aquifer, streams, or before reuse for irrigation purposes.
Responsible Water Strategy
The Ecovillage’s water efficiency strategies and alternative irrigation water supplies are effective and responsible ways to care for our planet. By implementing a responsible water strategy, the Ecovillage takes seriously its impact upon the environment and sets an example for future developments around the nation.